I recently saw a video interview in which Scott Fortunoff questioned Kaffe Fassett, Liza Prior Lucy, and Brandon Mably in her studio. I probably found the link on the Kaffe Fassett Collective FB page. I'm sorry I don't know how to locate it and post the link. Scott Fortunoff is an owner and executive of Jaftex Corporation which acquired Free Spirit Fabric after Coats announced its closing. During the very informal video, Scott mentioned that Kaffe prefers a different base fabric than other designers and Kaffe agreed. So that is what they use. I'm not remembering the terms and the specifics but they essentially print on different fabric because of the designer's adamant preference.
Scott has a blog that can be informative but sometimes is too specific for my time/interest. However is is amazing how little we actually know about the fabrics we all buy and enjoy and this man clearly has a different perspective than we as customers. He came to my attention when he gave a new sewing machine to a friend after she lost her home and everything in it when Hurricane Harvey blew through our area. It was a generous gift to a stranger form the goodness of his heart. I know he gave away quite a few machines. Hopefully some of these references will allow you to search for and look up whatever of it may be of interest to you.